Earthmoving scraper with tandem bowls

ABSTRACT

An earthmoving scraper having two bowls arranged one behind the other and actuating means to cause each bowl, independently of the other, to assume load, carry and discharge attitudes. Power for the scraper includes a forwardly disposed two-wheel tractor with an engine and a pair of rearwardly disposed wheels driven by a second engine.

Write ties alt [72] Inventors Rodney H. Anderson Naperville; John S. Logsdon, Chillicothe, both of, 111. [21] App]v No. 776,325 [22] Filed Nov.18,1968 [45] Patented June 19, 1971 [73] Assignee Caterpillar Tractor Co.

Peoria, 111.

[54] EARTHMOVING SCRAPER WllTlH TANDEM BOWLS 3 Claims, 9 Drawing Figs.

[52] U.S.C1 37/129, 37/127 [51] Int. Cl E021 3/64 [50] Field ofSearch 37/118, 124,126,127,128,129,D1G.3,4

[56] References Cited UNITED STATES PATENTS 629,826 8/1899 Taylor 37/127 Johnson H 37/8 Potgieteru. 37/4 Stuller. 37/8 Bechman.. .1 37/129 X Floyd 37/127 Ball et a1 t 37/127 Ball 37/127 Slate 37/DIG. 3 Armington et a1 37/127 H Clifford 1. 37/127 H Le Tourneau. 37/127 LaJoye 37/118 Primary ExaminerEdgar S, Burr Att0rney-Fryer, Tjensvold, Feix, Phillips and Lempio ABSTRACT: An earthmoving scraper having two bowls arranged one behind the other and actuating means to cause each bowl, independently of the other, to assume load, carry and discharge attitudes. Power for the scraper includes a forwardly disposed twowheel tractor with an engine and a pair of rearwardly disposed wheels driven by a second engine.

PATENTED M29197: 35891341 sum 3 0F 5 INVENTORS RODNEY H. ANDERSON JOHN S. LOGSDON ATTORNEYS PATENTEDJUHZQIQY 73,589.04].

SHEET u 0F 5' INVFN'H ms; RODNEY HANDERSON JOHN S. LOGSDON BY 4 W +-W PATENTEU JUN29 I971 SHEET 5 OF 5 INVFNTORf; RODNEY H ANDERSON JOHN s. LOGSDON ,91 Muzz -4rd,

EAR'II'IMOVIING SCRAIPIER WITH TANDEM BOWLS For many years earthmoving scrapers have been unable to accomplish full loading of the scraper bowl without assistance from another machine except possibly in the most favorable type of earth and under the most favorable circumstances. Loading has been accomplished by pushing the scraper with another tractor which adds to the overall operating expense. Scrapers have been combined in tandem units and multicn gine scrapers have been provided which, in some cases, are self loading. One self-loading scraper is the elevating type which is relatively complex and costly.

It is the object of the present invention to provide a self loading scraper having relatively large capacity which can be loaded in a short period of time and which is economical to manufacture and operate. Further objects and advantages of the invention and the manner in which it is carried into prac tice are made apparent in the following specification wherein reference is made to the accompanying drawings.

In the drawings:

FIG. l is a view in elevation of a tandem bowl scraper constructed in accordance with the present invention illustrating a portion of a two-wheel tractor which provides a part of the power for operating the scraper;

FIG. 2 is a plan view of the scraper shown in FIG. 1;

FIG. 3 is an enlarged fragmentary view partially in section showing the connection between the two scraper bowls;

FIG. 4 is a view in side elevation illustrating the two bowls in an attitude for loading the front bowl;

FIG. 5 is a similar view showing the front bowl loaded and the rear bowl in position for loading;

FIG. 6 is a view in side elevation of a modified form of the invention;

FIG. 7 is a plan view of FIG. 6;

FIG. 8 is a view in side elevation of a second modification of the invention; and

FIG. 9 is a plan view of the scraper shown in FIG. 8.

In FIGS. 1 and 2, the rear portion of a two-wheel tractor is generally indicated at It) and is shown as connected through a conventional hitch, gooseneck and steering assembly lll with a spreader tube l2 and draft arms 13 of a first scraper bowl I4. A second scraper bowl I5 is connected in tandem, by means presently to be described, with the first bowl and its rear end supported by wheels 16 which are driven by an engine l7 to supplement he power of the engine of the two-wheel tractor 10. The forward bowl I4 is pivotally connected with the draft arms ll3 as at lltl and may be raised and lowered by a pair of hydraulic lift jacks 20 which are connected between the spreader tube, as seen in FIG. 2, and a crossmember 22 in the bowl. An apron 24 shown as closing the forward end of the bowl may be raised to an open position by a conventional jack, means not shown, which swings a lever 26 about a pivotal connection with the gooseneck 28 causing a link 30 to raise the apron. A pair of bifurcated draft arms 32, one of which is best shown in FIG. 1, are rigidly connected to two points on each side of the forward bowl 14. These arms are pivotally connected to the rear bowl as at 34. FIG. 3 shows a spreader tube 36 disposed between the sidewalls at the rear upper portion of the forward bowl. This tube acts as a support through brackets 38 for a pair of bowl lift jacks 40. The rods of which, shown at 42, are pivoted with respect to a beam 44 which extends transversely with respect to rear scraper how] 15. A spreader tube 36 also supports an apron jack 45 which extends through suitable openings in the tube and is arranged to raise and lower a lever 46. A link 47 extends between lever 46 and the rear bowl apron shown at 48. The bowls l4 and 15 have forward cutting edges, shown at 49 and 50 respectively in FIG. 1, and the bowls have ejectors 52 and 54 respectively, the first of which is movable forwardly to eject the contents of the bowl by a jack shown at 56 in FIG. 3 and the second is similarly moved by ajaok shown at 58 in FIG. I.

The loading cycle of the two scraper bowls is shown in FIGS. 4 and 5. Generally, the first bowl 14 will be lowered by the mechanism previously described until its cutting edge en gages the earth as shown. During this cycle, the apron 24 is raised a short distance in accordance with conventional practice until the bowl is filled and raised to the carry position disclosed in FIGS. At this time, the rear bowl 15 is lowered until its cutting edge 50 engages the earth and, with the power of two engines and the traction advantage gained by the weight of the filled bowl M, the bowl 15 is quickly filled then raised for transportation to a selected fill pit where the ejectors are actuated for the usual disposition ofthe contents of the bowls.

A modification of the invention described above is shown in FIGS. 6 and 7 wherein the sidewalls ofa forward bowl 14 extend rearwardly to pivotal connections 60 with the sidewalls of a rear bowl l5. In this modification, the forward bowl has a floor and rear portion of arcuate configuration shown at 62 as pivoted to the bowl at 64. A pair ofjacks 66 swing the arcuate member between its closed carry position shown and its upward open position for ejecting the load. The rear bowl l5 has an apron 68 actuated by a jack 70 and has a conventional rearwardly disposed ejector 54 like the ejector 54 of FIG. I. The loading cycle of this modification of the invention will be much like the cycle illustrated in FIGS. 4 and 5. Another modification of tandem bowl scrapers is shown in FIGS. 8 and 9 wherein the front bowl has a pivoted bottom and backwall 62 corresponding to the bottom and backwall 62 of FIG. 6. Jacks 66 actuate the bottom and backwall about a pivot point 64'. At its rear edge, the member 62' is provided with a segmcnt of gear teeth 74 matching with a similar segment 76 on an apron 68' of the rear bowl. The rear bowl has a bottom member 78 pivoted as at 80 and adapted to be raised and lowered by a jack means not shown. When lowered, the cutting edge engages the earth until the bowl is filled. When it is desired to eject both loads, retraction of the jacks 66 opens the bottom of the forward bowl and, through the gear segments, the apron of the rearward bowl is simultaneously opened so that actuation of its ejector shown at 54" will eject its load in a conventional manner.

The scraper of the present invention has proven to be an efficient self-loading machine. For example, with two relatively small bowls, which are 16 cubic yards struck and 24 yards heaped and a combination of 900 horsepower to load each of the bowls, provided by a 500 horsepower engine on the tractor and a 400 horsepower engine on the rear wheels, the machine is comparable to and as fast or faster in loading as a large twoengine tractor scraper of the same capacity and with one or two pusher tractors assisting it during its loading cycle. The problem of jackknifing which is present where large tractor scraper units are connected in tandem, has also been eliminated and rolling resistance has been reduced by the elimination of wheels between the two scraper bowls.

What we claim is:

1. An earthmoving scraper comprising front and rear bowls, each bowl comprising sidewalls interconnected by a floor having a cutting edge, said bowls being disposed in a tandem relationship, a tractor disposed forwardly of said front bowl and having front wheels and a driving engine therefor, forward draft means connected between said front bowl and said tractor and providing for selective raising and lowering of said front bowl relative to said tractor and said rear bowl, rear wheels disposed behind said rear bowl and connected thereto, a second engine for driving the rear wheels and wheelless intermediate draft means connected between said front and rear bowls and providing for selective raising and lowering of said rear bowl relative to said front bowl, said intermediate draft means constituting the sole structural connection and support between said front and rear bowls whereby said bowls collectively are supported at the forward end by said tractor and are supported at the rearward end by said rear wheels and may be individually and sequentially lowered to a ground digging position and raised to a load carrying position.

end of the rear bowl with respect to the rearward end of the forward bowl.

3. The scraper of claim 2 in which each bowl has an apron closing its forward end and an ejector closing its rearward end. 

1. An earthmoving scraper comprising front and rear bowls, each bowl comprising sidewalls interconnected by a floor having a cutting edge, said bowls being disposed in a tandem relationship, a tractor disposed forwardly of said front bowl and having front wheels and a driving engine therefor, forward draft means connected between said front bowl and said tractor and providing for selective raising and lowering of said front bowl relative to said tractor and said rear bowl, rear wheels disposed behind said rear bowl and connected thereto, a second engine for driving the rear wheels and wheelless intermediate draft means connected between said front and rear bowls and providing for selective raising and lowering of said rear bowl relative to said front bowl, said intermediate draft means constituting the sole structural connection and support between said front and rear bowls whereby said bowls collectively are supported at the forward end by said tractor and are supported at the rearward end by said rear wheels and may be individually and sequentially lowered to a ground digging position and raised to a load carrying position.
 2. The scraper of claim 1 wherein said intermediate draft means comprises draft arms rigidly connected to the sidewalls of the front bowl and extending rearwardly to the sidewalls of the rear bowl, pivotal connections between the draft arms and the rear bowl, and power means to raise and lower the forward end of the rear bowl with respect to the rearward end of the forward bowl.
 3. The scraper of claim 2 in which each bowl has an apron closing its forward end and an ejector closing its rearward end. 